"""
209. Minimum Size Subarray Sum
Difficulty: Medium
https://leetcode.com/problems/minimum-size-subarray-sum/

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Given an array of positive integers nums and a positive integer
target, return the minimal length of a subarray whose sum is greater
than or equal to target. If there is no such subarray, return 0
instead.



Example 1:

Input: target = 7, nums = [2,3,1,2,4,3]
Output: 2
Explanation: The subarray [4,3] has the minimal length under the
problem constraint.

Example 2:

Input: target = 4, nums = [1,4,4]
Output: 1

Example 3:

Input: target = 11, nums = [1,1,1,1,1,1,1,1]
Output: 0



Constraints:

        • 1 <= target <= 10^9

        • 1 <= nums.length <= 10^5

        • 1 <= nums[i] <= 10^4



Follow up: If you have figured out the O(n) solution, try coding
another solution of which the time complexity is O(n log(n)).
"""


class Solution:
    def minSubArrayLen(self, target: int, nums: list[int]) -> int:
        window_sum = 0
        length = len(nums) + 1
        left = 0

        for right in range(len(nums)):
            window_sum += nums[right]
            while window_sum >= target:
                length = min(length, right - left + 1)
                window_sum -= nums[left]
                left += 1
        if length > len(nums):
            return 0
        return length